Siding panels serve a two-fold objective of protecting a structure from damaging elements such as sunlight, moisture, hail and strong winds as well as providing an aesthetically appealing external appearance to the structure. The siding must be capable of protecting the structure from blisteringly hot sunlight that can induce thermal expansion and unattractive buckling of the siding. Siding produced from polyvinyl chloride (PVC) with organic and inorganic fillers has been shown to minimize thermal expansion and prevent or minimize the buckling of the siding when the solar heat load upon the structure is the greatest. The thermally stable siding is blended with high quality materials and is extruded with sufficient thickness to withstand large diameter hail impacts without permanent deformation. Panel siding must also minimize the infiltration of moisture from heavy wind blown rains and should moisture find its way behind the siding an exit route must be available to avoid the growth of mold and to prevent the rotting of any cellulosic structural elements such as plywood siding and structural framing or the oxidation of ferrous support members.
In addition to the capacity to withstand thermal loading, hail impacts and provide an escape route for moisture, well designed and installed exterior siding must be capable of withstanding high wind loadings. Siding panels that allow wind to gain access to the back surface, or the surface adjacent to the building structure, can experience tremendous loads capable of literally peeling the siding from the building. Consequently, the ability to seal both the upper and lower edges of the siding panel against panel courses above and below is critical to protecting the panels from the effects of strong wind loads.
Numerous siding panel designs exist in the market place; however, all are either lacking in some functional aspect or are prohibitively expensive, difficult to install or require extensive training and costly tools for proper installation. The consequence of such involved training and the acquisition of expensive tools is that these costs must ultimately be passed onto the consumer in order for the installer to experience a profit from her labors.
The product disclosed herein overcomes the adversities posed by wind, hail, rain, sun and complex installation procedures with a simple design that requires little training or sophisticated tools to properly install. In addition, the handsome wood grain exterior surface is aesthetically appealing with the warm textured feel of natural wood yet produced from a composite material that is highly resistant to fading, chipping, moisture damage, cracking and damage by insects.
It is an object of the invention to provide a composite exterior siding panel that is thermally stable and that will not buckle or warp even under the most extreme solar heat loads.
It is another object of the invention to provide an aesthetically appealing exterior surface that replicates a natural wood grain.
It is another object of the invention to provide a composite exterior siding panel that is lightweight and easy to install by an untrained homeowner with standard tools.
It is another object of the invention to provide a composite exterior siding panel that is tough, durable and capable of withstanding impacts from large diameter hail.
It is another object of the invention to provide a composite exterior siding panel that facilitates drainage of moisture trapped between the paneling and the building structure through weep slots in the rear face of the panel that start near the first flat and proceed past the inflection point of the panel.
It is another object of the invention to provide a composite exterior siding panel that includes a locking leg extending rearwardly from the back face of the panel and that also extends nominally downwardly toward the bottom edge of the panel and that extends longitudinally along the entire length of the panel. The locking leg creates a pocket for insertion of the top edge of a second panel disposed below the first panel to precisely define the positional relationship between the first and second panels.
It is another object of the invention to provide a composite exterior siding panel with a top portion and a bottom portion of a panel separated by an inflection point such that the top and bottom portions diverge at approximately 5 degrees so that when the panel is secured to the side of a structure at the nail strip the panel portion below the inflection point extends away from the building surface. In addition, when installed against a structural wall, the bottom surface of the locking leg is separated from the structural wall by a gap of from 0.020 to 0.060. The gap between the locking leg and the surface of the wall facilitates movement of moisture from upper panel courses to lower panel courses and ultimately to ground level thereby limiting contact with building surfaces that would deteriorate if exposed to the moisture for extended periods of time.